Python version

'python=3.10.12 (main, Jun 11 2023, 05:26:28) [GCC 11.4.0]'
'os=Linux-5.15.90.1-microsoft-standard-WSL2-x86_64-with-glibc2.35'
'numpy=1.26.1'
ldf is not supported
xls is not supported
xlsx is not supported
yaml is not supported
'asammdf=7.3.14'

Code

MDF version

4.10

Code snippet

with MDF(filename) as mdf_file:
    df = mdf_file.to_dataframe("someExistingChannelName")

Traceback

Traceback (most recent call last):
  File "parse_mf4.py", line 83, in <module>
    df: DataFrame = get_df(logfile, "someExistingChannelName")
  File "parse_mf4.py", line 69, in get_df
    return mdf_file.to_dataframe(channel_name)
  File "venv/lib/python3.10/site-packages/asammdf/mdf.py", line 4535, in to_dataframe
    mdf = self.filter(channels)
  File "venv/lib/python3.10/site-packages/asammdf/mdf.py", line 2146, in filter
    gps = self.included_channels(channels=channels)
  File "venv/lib/python3.10/site-packages/asammdf/blocks/mdf_v4.py", line 8134, in included_channels
    group, idx = self._validate_channel_selection(name)
  File "venv/lib/python3.10/site-packages/asammdf/blocks/mdf_common.py", line 87, in _validate_channel_selection
    raise MdfException(f'Channel "{name}" not found')
asammdf.blocks.utils.MdfException: Channel "s" not found

Description

When passing a single string as the channels parameter to MDF.to_dataframe() or MDF.filter(), an error is returned that the channel cannot be found. This is due to the fact, that the channels parameter is iterated in blocks/mdf_v4.included_channels() which results in iterating the string by its characters and leads to searching for a channel name with only the first letter of the provided string.

Of course, if you take a look at the definition of ChannelType, you see that it accepts a Sequence[str] rather than a str, but the documentation clearly states, that a single channel name string is allowed:

channels : list list of items to be filtered (default None); each item can be :

a channel name string

(channel name, group index, channel index) list or tuple

(channel name, group index) list or tuple

(None, group index, channel index) list or tuple

So it might be useful to change the documentation in that regard.

danielhrisca / asammdf